1. The Field of the Invention
The invention relates generally to the integration of broadcast television programming with other multimedia content. More specifically, the invention relates to methods and apparatus for integrating broadcast television images with pages available over the Internet.
2. Background and Related Art
The Internet is a worldwide collection of networks and gateways. The Internet includes a backbone of high-speed data communication lines between major nodes or host computers, consisting of thousands of commercial, government, educational, and other computer systems. The Worldwide Web (the Web) is composed of a vast number of uniquely addressed “pages” of information available on the Internet. The unique addresses, conventionally known as Universal Resource Identifiers (URIs), make it easy to establish links between related pages, and between pages and other information resources on the Web. Common types of URIs include URLs (Universal Resource Locators) and URNs (Universal Resource Names).
Information on a given page may be linked to related information on a second page by providing a “hyperlink,” or “link,” specifying the URI of the second page. Such links are typically represented as highlighted text or graphic representations that may be selected using a mouse-type pointer (a “mouse”). Users move between pages on the Internet by selecting links according to the user's interest. This method of moving from page to page on the Internet in search of information is commonly referred to as “surfing the Net.”
The Web has become a popular resource for information relating to almost any subject. The growth of this popularity has been greatly enhanced by the development of standard generalized markup languages (SGML), in particular the hypertext markup language (HTML) and, more recently, the Extensible Markup Language (XML). Markup languages define the format of Web documents by establishing the syntax and placement of special, embedded instructions that tell Web browsers how to display the contents of a document. HTML and XML also interconnect Web pages and other information resources using hyperlinks. HTML is presently the most popular markup language used to author Web content. The following discussion therefore focuses on HTML, although the concepts discussed apply equally to other markup languages.
FIG. 1 (prior art) is a flowchart 100 depicting how a conventional browser or Internet terminal renders a stream of HTML data 110 to display a Web page 120. Beginning at step 130, a software object called an HTML parser parses HTML data 110. The term “software object” is used here in the context of object-oriented programming, and refers to a variable comprising both routines and data that is treated as a discrete entity.
Parsing HTML data 110 produces a series of HTML tags and attributes 140. Tags are code that identifies an element in a document, such as a heading or a paragraph, for the purposes of formatting, indexing, and linking information in the document. Attributes are name-value pairs within a tagged element that modify certain features of that element. These features include color, size, position, and the size and style of fonts.
Next, a software object typically referred to as a “document builder” 150 interprets tags and attributes 140. The interpretation results in the creation of a document data structure 160 that contains all of the formatting and content information required to render HTML page 120. The content information can include links to other information resources, such as video, images, and other Web pages to be displayed within the confines of HTML page 120. Finally, a graphics processor and related software interpret data structure 160 to render the image of HTML page 120 (the HTML document) for display.
Internet terminals, such as those pioneered by WebTV Networks, Inc., provide Web access without a traditional personal computer. Internet terminals (also commonly referred to as set-top boxes) provide Web access using an ordinary television (TV) set as a display and a remote control or wireless keyboard for user input. These Internet terminals allow viewers to view Web content, watch television, or simultaneously do both by displaying broadcast TV within a window of a Web page. TV viewed within a Web page is not part of the HTML document defining the page, but must be incorporated separately using dedicated software. While the results are acceptable, there is nevertheless a need for a simpler method of merging HTML and broadcast TV content.
On occasion, it is desirable to display graphic images over broadcast video without completely obscuring the video. Such a mode of operation permits the viewer to continue to watch, for example, a favorite television program, while nevertheless monitoring the progress of e.g. a breaking news story or a live game score. Conventional Internet terminals, such as that available from WebTV, Inc., offer this functionality. However, the melding of HTML content and broadcast television is currently a complex process. Further, conventional Internet terminals do not support the use of television in the background of an HTML document. The need for a simple means of combining HTML and broadcast TV content therefore encompasses a need for a method that supports broadcast TV background for Web pages.